It didn’t take long—my Sprinter van was “already broken.” After letting it sit in the PA cold (we were around -10), I went to start it and the battery was dead. On these vans, the battery isn’t up under the hood like my Toyotas; it’s under the seat, and even doing something simple turns into a whole thing when it’s freezing. The computers went dark and it kept trying to crank (click click click), so I had to yank the quick disconnect in the dash, then eventually tear into the floor panels to get to the battery and put it on a little 2-amp Harbor Freight charger. After about 20 hours on the charger it was only around 12.66 volts, which had me thinking the battery might be shot (and of course it’s a ~$300 battery). I got it buttoned up, let it warm up a bit, and the van fired right up—just threw a “stop vehicle leave running” warning because the battery had been too low. A couple days later I checked voltage again and saw 12.08, but I learned something important: as soon as you unlock/open the door, the van wakes up a bunch of systems and starts drawing power. Let it sit and settle, and the voltage made a lot more sense (about 12.3 at 14°). Takeaway: if you’re leaving a Sprinter outside in the cold, disconnect the battery, and I’m still bringing a jump pack on the road just in case.